King Air C90GTi, Руководство по подготовке пилотов

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Operation with the FUEL PRESS
a n n u n c i a t o r o n i s l i m i t e d t o 1 0
h o u r s , a f t e r w h i c h t h e e n g i n e -
driven high pressure pump must be
overhauled or replaced. When op-
erating with Aviation Gasoline base
f u e l s , o p e r a t i o n o n t h e e n g i n e -
driven high pressure pump alone is
permitted up to 8,000 feet for a pe-
r i o d n o t t o e x c e e d 1 0 h o u r s .
Operation above 8,000 feet requires
boost or operation of crossfeed.
The following Fuel Management Limitations,
listed in the Limitations section of the
POH ,
pertain to fuel system boost pumps.
B o t h b o o s t p u m p s m u s t b e o p e r a bl e p r i o r
t o t a k e o ff .
Operation is limited to 8,000 feet when op-
e r a t i n g o n av i a t i o n g a s o l i n e w i t h b o o s t
pumps inoperative.
Operation with the FUEL PRESS annunci-
ator on is limited to 10 hours between main
e n g i n e - d r ive n f u e l p u m p ove r h a u l o r r e -
placement.
FUEL TRANSFER PUMPS
Fuel level in the nacelle tank is automati-
cally maintained at near full capacity dur-
i n g n o r m a l o p e r a t i o n b y a f u e l t r a n s f e r
system, whenever the fuel level in the na-
celle tank drops by approximately 10 gal-
l o n s . S u b m e r g e d, e l e c t r i c a l l y - d r i v e n ,
impeller pumps located in the wing center
section tanks provide the motive force for
f u e l t r a n s f e r f r o m w i n g t a n k s t o n a c e l l e
tanks. The transfer pumps are controlled by
float-operated switches on the nacelle tank
fuel quantity transmitters.
Fuel is transfer red automatically when the
TRANSFER PUMP switches are placed in
AUTO, unless the nacelle tanks are full. As
the engines burn fuel from the nacelle tanks
(61 gallon capacity each tank), fuel from the
wing tanks is transfer red into the nacelle
tanks each time the nacelle tank levels drop
approximately 10 gallons. The nacelle tanks
will f ill until the fuel reaches the upper trans-
fer limit and a float switch turns the TRANS-
FER PUMP off.
A pressure switch, located in the fuel trans-
fer line, will automatically turn off the trans-
fer pump if a preset pressure is not obtained
within approximately 30 seconds after the
pump is turned on, or if the transfer pump pres-
sure drops below a preset pressure due to empty
wing tanks or pump failure. For example, when
132 gallons of fuel (each side) are used from
the wing tanks (132 gallons usable each side),
the pressure sensing switch reacts to a pres-
sure drop in the fuel transfer line as the wing
tanks are exhausted of fuel. After 30 seconds,
the transfer pump shuts off and the respective
yellow NO FUEL XFR annunciator on the an-
nunciator panel illuminates.
The NO FUEL XFR annunciators will illu-
minate for the reasons mentioned: no pres-
sure after 30 second time delay due to empty
wing tanks or transfer pump failure. The NO
FUEL XFR annunciator also functions as an
operation indicator for the transfer pump
during preflight. A TRANSFER TEST switch
(placarded ENGINE L and ENGINE R) is
provided to verify the operation of each pump
when its nacelle tank is full. Holding the
Transfer Test switch in the test position (ei-
ther L or R) will activate the transfer pump
and pressure sensor. In the test mode, the 30-
second delay is by-passed, resulting in im-
m e d i a t e i n d i c a t i o n s . T h e N O F U E L X F R
annunciator will momentarily illuminate and
the MASTER CAUTION flasher will also
begin flashing. The NO FUEL XFR annun-
ciator will extinguish when fuel pressure to
the sensor reaches a minimum pressure of
2.5 psi. If the transfer pump is operating, use
of the transfer test will not be possible.
CAUTION
KING AIR C90GTi/C90GTx PILOT TRAINING MANUAL
5-5
FOR TRAINING PURPOSES ONLY
5
FUEL
SY
STEM